Nineteenth century chrome yellow and chrome deep from Winsor & NewtonTM     

Vanessa Otero  Joana V. Pinto  Leslie Carlyle  Márcia Vilarigues  Marine Cotte 《文物保护研究》2017,62(3):123-149

The Winsor & Newton^TM (W&N) nineteenth century archive database includes digitised images of hand-written instructions and workshop notes for the manufacture of their artists’ materials. For the first time, all 183 production records for yellow lead chromate pigments were studied and evaluated. They revealed that W&N produced essentially three pigment types: lemon/pale based on mixed crystals of lead chromate and lead sulphate [Pb(Cr,S)O₄]; middle on pure monoclinic lead chromate [PbCrO₄]; and deep that contains the latter admixed with basic lead chromate [Pb₂CrO₅]; accounting for 53, 22, and 21% of the production, respectively. Production records for primrose (4%) were also included since the formulation results in mixed crystals with a high percentage of lead sulphate, which, according to the literature, leaves it more prone to degradation. Each pigment type is characterised by only one or two main synthetic pathways; process variations reveal a systematic and thorough search for a high-quality durable product. A comparison of the chemical composition of pigment reconstructions with early W&N oil paint tubes showed that their records entitled ‘pale’ and ‘lemon’ correlated with the pigment in their tube labelled chrome yellow and, ‘middle’ and ‘deep’ with the label chrome deep. Lemon and middle pigment formulations were made into oil paints to assess their relative photo-stability. The degradation process was followed by colorimetry and was studied by synchrotron radiation-based techniques. Based on the X-ray absorption spectroscopy data, the possibility for creating a stability index for chrome yellows is discussed.  相似文献   

红外光谱Excel处理技术及其应用     

庞新安 《实验技术与管理》2007,24(6):71-73

红外光谱技术是一种高效、快速的现代分析技术,而Microsoft Excel是一个功能强大的数据处理软件,两者均在很多领域得到了广泛应用。该文利用苯甲酸红外光谱实验数据为操作对象,介绍了用Mi-crosoft Excel软件处理该类型实验数据的详细步骤,包括数据引用方法、图表绘制及其修饰等相关技术。  相似文献   

人流量统计系统设计   总被引：2，自引：0，他引：2  

何小映  何红 《中国科技信息》2007,(14):97-98

本统计系统用于统计某个超市的客源流量。该系统具有智能功能,一方面能适时统计该超市的实际人数,自动判断顾客是进入还是离开超市,如果进入则进行加计数,相反则进行减计数,计得的人数通过显示器显示出来。另一方面能统计某天进入超市的总人数,而且能将每天的人流量保存起来,供需要时查询。该系统具有结构简单、成本低廉、计数准确的特点。不仅适用于超市,还适用于其它需要进行人数统计的场合。  相似文献   

Local Spiral Curves Simulating Based on Hough Transformation and Center Auto-Locating of Developing Typhoon     

王萍郭传澍  罗颖昕 《天津大学学报(英文版)》2006,12(2):142-146

In the developing phase of typhoon formation, the spiral belt partly emerges in satellite cloud images. This research starts from images and moves on to graphics and then to representation and recognition. Following this route, local spiral cloud belt is segmented from the raw images using image segmentation, the spiral information is extracted using mathematic morphology, and local spiral curves are detected using Hough transformation. The problem of center locating of developing typhoon has finally been solved through a search algorithm of spiral curve. For No. 99082008 cloud image, the result produced by the algorithm in this paper is at 122. 3 degree west longitude, 17.5 degree north latitude. The real typhoon center location was at 122.4 degree west longitude, 18 degree north latitude.  相似文献   

钙镁电气石检测特征探析     

江富建 《南阳师范学院学报》2002,1(2):75-77

在宝石检测中发现，钙镁电气石呈黄绿色，与祖母绿相似。利用折射仪、红外光谱仪等手段测试确定为电气石。采用X射线衍射和电子探针分析（Cr2O含量仅0．08％），结果定名为钙镁电气石。它的主要鉴定特征与不同变种的电气石近似，与其它相似宝石的特性特征区别明显。  相似文献   

“病态”IR光谱图的产生及改进方法     

张鲁西 《湖南师范大学教育科学学报》1997,(5)

本文就因实验方法不当而导致IR谱图失真（即称“病态”IR光谱）的原因加以分析提出改进的方法．  相似文献   

飞机红外热波无损检测中损伤埋藏深度的计算方法     

苏义鑫  魏敦军  杨小林 《唐山师范学院学报》2007,29(5):4-6

复合材料及构件在新型飞机中的使用不断增多,用常规无损检测的方法难以准确获得复合材料损伤部位的埋藏深度。结合军用飞机复合材料构件损伤检测的实际需要,研究了飞机红外热波无损检测新技术中损伤部位埋藏深度的计算思想及计算机实现方法,并给出了具体实例。  相似文献   

超高温多相流燃烧物质红外辐射特性的计算     

王明军  张小安  张辉 《咸阳师范学院学报》2006,21(6):18-21

超高温多相流燃烧研究在快速飞行的航天飞行器应用领域中至关重要。本文依据固体火箭发动机喷焰超音速射流燃烧中产生大量的氧化铝固体颗粒群和多组分气体实际应用为背景,结合粒子浓度的实际特征,建立固体颗粒群粒子浓度分布模型,并根据粒子质量加权平均直径经验公式,计算它们在波长3～5!m范围内的空间红外辐射强度随温度场的分布。同时对燃烧过程中产生的几种多组分接近完全气体,计算其热传导系数,为进一步开展相关红外特性研究和建立用于超高温多相燃烧红外辐射理论模型提供重要依据。  相似文献   

混凝土损伤的红外热像检测     

徐胜林  宋显辉 《实验室研究与探索》2007,(11)

本文利用混凝土的损伤与自身热导率变化的关系,借助红外热像仪,通过分析混凝土试样表面温度场分布的情况来判断混凝土试样内部损伤的区域和发展程度。  相似文献   

一个物理综合实验的设计与实践--弹簧振子加速度的红外遥测     

聂士忠 《实验室研究与探索》2006,25(1):31-33

介绍我们新开发的一个综合性实验,它主要包括拉力传感器、由LM331组成的V/F和F/V变换电路以及红外发射和接收装置等,以实现对弹簧振子加速度的红外遥测。利用计算机USB数据采集器进行数据采集和处理,包括计算弹簧振子的速度和位移、系统的弹性势能、重力势能、动能和总机械能,并绘制机械能变化曲线,由此验证了弹簧振子系统的机械能守恒。本实验项目在提高学生学习的主动性和创新能力方面取得了较好的效果。  相似文献